Separate byteoffset ast and located ast

core/src/error.rs

@@ -1,11 +1,10 @@
-use ruff_text_size::TextSize;
-use std::error::Error as StdError;
+use crate::{text_size::TextSize, Location};
 use std::fmt::Display;
 
 #[derive(Debug, PartialEq, Eq)]
 pub struct BaseError<T> {
     pub error: T,
-    pub location: TextSize,
+    pub offset: TextSize,
     pub source_path: String,
 }
 
@@ -17,11 +16,11 @@ impl<T> std::ops::Deref for BaseError<T> {
     }
 }
 
-impl<T> StdError for BaseError<T>
+impl<T> std::error::Error for BaseError<T>
 where
-    T: StdError + 'static,
+    T: std::error::Error + 'static,
 {
-    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
         Some(&self.error)
     }
 }
@@ -35,7 +34,7 @@ where
             f,
             "{} at byte offset {}",
             &self.error,
-            u32::from(self.location)
+            u32::from(self.offset)
         )
     }
 }
@@ -51,7 +50,7 @@ impl<T> BaseError<T> {
     {
         Self {
             error: obj.error.into(),
-            location: obj.location,
+            offset: obj.offset,
             source_path: obj.source_path,
         }
     }
@@ -62,4 +61,64 @@ impl<T> BaseError<T> {
     {
         BaseError::from(self)
     }
+
+    pub fn into_located<U>(self, locator: &str) -> LocatedError<U>
+    where
+        T: Into<U>,
+    {
+        todo!()
+    }
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct LocatedError<T> {
+    pub error: T,
+    pub location: Location,
+    pub source_path: String,
+}
+
+impl<T> LocatedError<T> {
+    pub fn error(self) -> T {
+        self.error
+    }
+
+    pub fn from<U>(obj: LocatedError<U>) -> Self
+    where
+        U: Into<T>,
+    {
+        Self {
+            error: obj.error.into(),
+            location: obj.location,
+            source_path: obj.source_path,
+        }
+    }
+
+    pub fn into<U>(self) -> LocatedError<U>
+    where
+        T: Into<U>,
+    {
+        LocatedError::from(self)
+    }
+}
+
+impl<T> Display for LocatedError<T>
+where
+    T: std::fmt::Display,
+{
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(
+            f,
+            "{} at row {} col {}",
+            &self.error, self.location.row, self.location.column,
+        )
+    }
+}
+
+impl<T> std::error::Error for LocatedError<T>
+where
+    T: std::error::Error + 'static,
+{
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        Some(&self.error)
+    }
 }

core/src/lib.rs

@@ -8,8 +8,13 @@ pub mod marshal;
 mod mode;
 
 pub use bytecode::*;
-pub use error::BaseError;
-pub use location::Location;
+pub use error::{BaseError, LocatedError};
+pub use location::{Location, LocationRange};
 pub use mode::Mode;
 
 pub use ruff_text_size as text_size; // re-export mandatory and frequently accessed dependency
+
+// FIXME: temp code
+pub fn to_location(offset: &text_size::TextSize, source: &str) -> Location {
+    todo!()
+}

core/src/location.rs

@@ -1,9 +1,6 @@
-#[cfg(feature = "serde")]
-use serde::{Deserialize, Serialize};
-
 /// Source code location.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Location {
     pub(super) row: u32,
     pub(super) column: u32,
@@ -96,6 +93,8 @@ impl Location {
     }
 }
 
+pub type LocationRange = std::ops::Range<Location>;
+
 #[cfg(test)]
 mod tests {
     use super::*;